(In reply to xujing from comment #39) > I'm sorry, I misled you. I think there is an ABBA deadlock issue in some > scenarios. > > If I have a c++ dynamic library(named libA.so) that contains a global > object, the global object will call the post-constructor at initialization > and hold it's own lock(named A_lock) when dlopen loads libA.so. Assume that > two threads execute the following process： > Thread1:dlopen(libA.so) => hold dl_load_lock => load libA.so => init > global > object from libA.so => wait for hold A_lock > Thread2:my own code hold A_lock => pthread_create => > _dl_allocate_tls_init > => wait for hold dl_load_lock > In this case, an ABBA deadlock occurs. Is this a bug?
yes i think this should work (it is a lock ordering issue between a user and libc internal lock, which is only possible if user code is run while a libc lock is held) note that if you replace pthread_create with dlopen that deadlocks too. so it's still bug 15686. but it may be more common than i expected. i think we need to look at fixing that bug. (fixing the dynamic tls race of this bug without locks in pthread_create is very hard, so i don't think we can revert the quoted patch) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1863162 Title: Inconsistency detected by ld.so: dl-tls.c: 493: _dl_allocate_tls_init: Assertion `listp->slotinfo[cnt].gen <= GL(dl_tls_generation)' failed! To manage notifications about this bug go to: https://bugs.launchpad.net/glibc/+bug/1863162/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
